I'm using Yaley Resin for this which is a type of polyester resin. It is mixed using a catalyst.
I will be adding the mixing instructions as a tab on the site for easy reference.

The first thing you need to know about this type of resin is USE IT OUTSIDE!!!
There are fumes, serious fumes, that can be harmful when inhaled. Be sure you are in a very well ventilated area when you use this. Your yard or an open garage with a fan. Do Not use this inside!

That said the mixing of this resin works very differently than EasyCast. You need to know how deep your resin will be when it's poured and how much resin you'll need. Also, it will change if you are doing multiple layers.

If you're pouring a piece that is 1/4 inch deep you will want to mix your resin using 1 oz of resin and 9 drops of catalyst. If you need more resin than 1 oz you would double the recipe: 2 oz of resin and 18 drops of catalyst and so on.

If you're pouring a piece that is 1/2 inch deep you will mix 1 oz of resin and 5 drops of catalyst.
The deeper the resin is the more heat will build up and you'll need less catalyst.

If you are making something very deep you will want to work in layers.
The first layer might be 1/4 inch deep using 1 oz of resin and 5 drops of catalyst. But when you mix the resin for the second layer, even though it might still be 1/4 inch deep, you would mix 1 oz of resin with only 4 drops of catalyst. The heat from the first layer will help the second layer set and not need so much catalyst. The third layer would only need 1 oz of resin and 3 drops of catalyst!

When mixing resin that uses a catalyst you color or add glitter to the resin before you add the catalyst.
Once the catalyst has been added your working time starts and you don't want to waste it mixing colors. So you add the resin to your cup and mix in the coloring or glitter until you get it the way you like it. Then you add the catalyst in.

You can also embed things in this type of resin. That works the same as other varieties of resin.
Be sure to seal paper items with Mod Podge!
You'll have to experiment to see which things float and sink as the viscosity (thickness) of this type of resin is different than Epoxy Resin (like EasyCast). It also "gels" quicker which means you might expect things like glitter to sink and the resin will thicken more quickly than you expect so the glitter might float instead.

This resin will need 24-72 hours to harden completely before removing from the mold. It will also need additional time for the chemical smell to fade.

As a side note: (in my opinion) the finished resin pieces seem to be lighter weight than EasyCast and when left clear the resin is much more clear and has less air bubbles than EasyCast.
The finished pieces did retain the chemical smell for a few days though and had to be left to air out making it less suitable for immediate use once set. The smell did go away after a few days (less than a week) of being left in the garage.

Start with measuring the resin...

Pour it into your mixing cup...
This is when you would add color or glitter!